As #Signal has had severe problems recently due to its centralised nature, here are some decentralised libre alternatives with Fediverse accounts:
➡️ @snikket_im - Initiative to give XMPP a consistent look and feel on instances and apps, to make it more attractive to new users
➡️ @xmpp - XMPP standards foundation
➡️ @delta - Decentralised messaging through email
➡️ @matrix - Best known for the Element client
➡️ @briar - Peer-to-peer encrypted messaging
➡️ @Jami - Peer-to-peer Skype alternative
That's not what a "single point of failure" is. The Fediverse has many points of (partial) failure - i.e. specific instances can go down and frustrate users of those instances for sure.
But when Signal (or any other centralized system) goes down, that's down for absolutely everyone on that platform.
That kind of situation is impossible on a decentralized network.
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